The Water Supply (Water Quality) Regulations 2000

regulation 40

SCHEDULE 5AMENDMENT OF THE WATER SUPPLY(WATER QUALITY) REGULATIONS 1989

The amendments to the 1989 Regulations referred to in regulation 40 are—

(a)after regulation 13, the insertion of the following regulation—

Frequency of sampling for particular organisms and substances

13A.(1) Subject to paragraphs (5) and (6), in each of the years 2001, 2002 and 2003, a water undertaker shall take, or cause to be taken, from its sampling points or, as the case may be, its supply points, for analysis for testing against the concentrations and values specified in column (2) of Table 4A for the organisms and substances listed in column (1) of that Table, not less than the number of samples specified in paragraphs (2) and (3).

(2) In respect of supply points and the supply of a volume of water within a range shown in column (3) of that Table, the number is that shown in column (4) of that Table with the prefix “S” as applicable to a volume within that range.

(3) In respect of sampling points and the supply of water to an estimated population within a range shown in column (5) of that Table, the number is that shown in column (6) of that Table with the prefix “S” as applicable to a population within that range.

(4) In each of those years samples shall be taken at regular intervals throughout the year.

(5) Where—

(a)a programme of work has been approved or is treated as approved under regulation 41 (transitional provision: programmes of work) of the Water Supply (Water Quality) Regulations 2000; or has otherwise been agreed by the Secretary of State; and

(b)at least one of the steps required to be taken in accordance with that programme—

(i)relates to an organism or substance listed in column (1) of Table 4A; and

(ii)remains to be completed,

the number of samples to be taken in any period of twelve months beginning with the date on which the programme was approved, treated as approved, or agreed (as the case may be) and ending on the day on which the last of those steps is completed, for analysis for testing for that organism or substance, may be the number shown in column (4) or, as the case may be, column (6) of that Table with the prefix “R”.

(6) Where analysis of the samples taken by a water undertaker in 2001 or 2002 in accordance with this regulation has established a concentration or value in respect of an organism or substance listed in column (1) of Table 4A that is significantly lower than the prescribed concentration or value, the number of samples to be taken in 2002 or 2003, respectively, for analysis for testing for that organism or substance, may be the number shown in column (4) or, as the case may be, column (6) of that Table with the prefix “R”.;

(b)after regulation 20, the insertion of the following regulation—

Additional testing for particular parameters

20A.  The samples taken in accordance with regulation 13 shall additionally be tested against the concentrations specified in column (2) of Table 4B.;

(c)in regulation 21 (collection and analysis of samples)—

(i)in paragraph (2), the insertion, after “means”, of “subject to paragraph (3)”; and

(ii)the addition, at the end, of the following—

(3) In relation to each of the parameters and other substances listed in column (1) of Table 4B, paragraph (2)(d) shall have effect as if for sub-paragraph (iii) there were substituted the requirements of regulation 21A.;

(d)after regulation 21, the insertion of the following regulation—

Method of analysis of samples for particular parameters and substances

21A.(1) The method of analysis used for testing for a parameter or other substance listed in column (1) of Table 4B against the concentrations in column (2) of that Table must be capable, at the time of use—

(a)of measuring concentrations with the trueness and precision specified in relation to that parameter or substance in columns (3) and (4) of Table 4B; and

(b)of detecting the parameter or substance at the limit of detection specified in relation to it in column (5) of that Table.

(2) For the purposes of paragraph (1)—

  • “limit of detection” is to be calculated as—

    (a)

    three times the relative within batch standard deviation of a natural sample containing a low concentration of the parameter or substance; or

    (b)

    five times the relative within batch standard deviation of a blank sample;

  • “precision” (the random error) is the standard deviation (within a batch and between batches) of the spread of results about the mean; and

  • “trueness” (the systematic error) is the difference between the mean value of a large number of repeated measurements and the true value.;

(e)in regulation 29(1)(f), after the words “Part IV of these Regulations”, the insertion of “, other than regulation 13B,”; and

(f)the insertion, after Table 4 in Schedule 3, of the following Tables—

TABLE 4A

SAMPLING FOR PARTICULAR ORGANISMS AND SUBSTANCES

(1)(2)(3)(4)(5)(6)
Organism or substanceConcentration or value and unit of measurementVolume of water supplied m3/dAnnual sampling frequencyEstimated population of water supply zoneAnnual sampling frequency
*

where the water originates from, or is influenced by, surface waters

Benzene1.0 μg/l
Bromate10 μgBr03/l
Clostridium perfringens* (including spores)<999S2 or R1<4,999S2 or R1
01,000 −49,999S4 or R15,000–50,000S4 or R1
Number/100ml> 50,000S8 or R2
1,2 dichloroethane3.0 μg/l
Enterococci0 Number/100ml
Nitrite0.10 mgNO2/l

TABLE 4B

PARAMETERS AND SUBSTANCES IN RELATION TO WHICH,SUBJECT TO REGULATION 21A, METHODS OF ANALYSISMUST SATISFY PRESCRIBED CHARACTERISTICS

(1)(2)(3)(4)(5)
Parameter or other substanceConcentration and unit of measurementTrueness % of concentrationPrecision % of concentrationLimit of detection % of concentration
*

Trueness, precision and limit of detection apply to the individual substances specified at 50% of the concentration in column (2)..

Antimony5.0 μgSb/l252525
Arsenic10 μgAs/l101010
Benzene1.0 μg/l252525
Boron1.0 mgB/l101010
Bromate10 μgBrO3/l252525
Copper2.0 μgCu/l101010
1,2 dichloroethane3.0 μg/l252510
Lead25 μgPb/l101010
Nickel20 μgNi/l101010
Nitrite (ex works)0.1 mgNO2/l101010
Tetrachloroethene*10 μg/l252510
Trichloroethene*10 μg/l252510